absolute threshold

Examples of absolute threshold in the following topics:

• Sensory Absolute Thresholds

  • The absolute threshold is the lowest intensity at which a stimulus can be detected.
  • Smell is not the only sense with absolute thresholds.
  • Every sense has an absolute threshold.
  • Expectations can also affect the absolute threshold.
  • Light at the end of the tunnel: the absolute threshold for vision

• Sensory Difference Thresholds

  • The just-noticeable difference (JND), also known as the difference limen or differential threshold, is the smallest detectable difference between a starting and secondary level of sensory stimulus.
  • The absolute threshold is the minimum volume of the radio we would need in order to notice that it was turned on at all.
  • The difference threshold is the amount of stimulus change needed to recognize that a change has occurred.
  • If someone changes the volume of a speaker, the difference threshold is the amount it has to be changed in order for listeners to notice a difference.

• Somatosensation: Pressure, Temperature, and Pain

  • These receptors are not good indicators of absolute temperature, but they are very sensitive to changes in skin temperature.
  • Functionally, nociceptors are specialized, high-threshold mechanoceptors or polymodal receptors.

• Stages of the Action Potential

  • The level of stimulation that a neuron must receive to reach action potential is known as the threshold of excitation, and until it reaches that threshold, nothing will happen.
  • Once the electric gradient has reached the threshold of excitement, the "downswing" of repolarization begins.
  • A neuron must reach a certain threshold in order to begin the depolarization step of reaching the action potential.

• Neurotransmitters

  • An action potential is necessary for neurotransmitters to be released, which means that neurons must reach a certain threshold of electric stimulation in order to complete the reaction.
  • A neuron has a negative charge inside the cell membrane relative to the outside of the cell membrane; when stimulation occurs and the neuron reaches the threshold of excitement this polarity is reversed.

• Eating Disorders

  • Eating Disorders Not Otherwise Specified (EDNOS) is an eating disorder that does not meet the criteria for anorexia nervosa or bulimia nervosa, and includes binge eating disorder, night eating syndrome, and sub-threshold syndromes in which some, but not all, of the symptoms of the more formally defined eating disorders are present.
  • Individuals with EDNOS usually fall into one of three groups: sub-threshold symptoms of AN or BN, mixed features of both disorders, or extremely atypical eating behaviors that are not characterized by either of the other established disorders.

• Mechanics of the Action Potential

  • If the membrane potential reaches -55 mV, it has reached the threshold of excitation.
  • Synaptic responses summate in order to bring the postsynaptic neuron to the threshold of excitation, so it can fire an action potential (represented by the peak on the chart).

• Bipolar Disorders

  • It is estimated that roughly 1% of the adult population suffer from bipolar I, a further 1% suffer from bipolar II or cyclothymia, and somewhere between 2% and 5% percent suffer from "sub-threshold" forms of bipolar disorder.

• Cognitive Development in Adolescence

  • Adolescents are more likely to engage in relativistic thinking—in other words, they are more likely to question others' assertions and less likely to accept information as absolute truth.
  • Through experience outside the family circle, they learn that rules they were taught as absolute are actually relativistic.

• Eating Disorders

  • Individuals with EDNOS usually fall into one of three groups: sub-threshold symptoms of another eating disorder, mixed features of different eating disorders, or extremely atypical eating behaviors that are not characterized by any of the other established disorders.